Ned Simmons from another forum just pointed out that it may be cheaper to machine a flat on the screw, like a standard spring hook shown on page 3114 of the Mcmaster catalog www.mcmaster.com. For example, see image of Mcmaster part # 9634k13. This should allow the screw anchor to clear the hook curvature of the spring.
If I do this, the flat will only be about .0625" thick in order to clear the spring hook. The spring will only have about 40 to 50 pounds on it so as long as a thin flat like that can be machined without problems, it may be a viable option.
Which would be cheaper, machining a slot, or milling a flat like a standard spring anchor and then drilling the hole ?
Thanks again guys,